Geomapping

library(tidyverse)
library(kableExtra)
library(sf)
library(ggspatial)

1 Loading the Map Data Files

proj_dir = "/Volumes/GDRIVE_SSD/homes/alex/datascience/698_CAPSTONE_2021_FALL"

working_dir = paste0(proj_dir, "/", "project_code/Part2_GeoMapping/")

data_dir = paste0(proj_dir, "/project_data/")

setwd(working_dir)

raleigh_corporate_limits_file = paste0(data_dir, "Corporate_Limits.geojson")

cityworks_potholes_file = paste0(data_dir, "Cityworks_Potholes.geojson" )

raleigh_parks_file = paste0(data_dir, "Raleigh_Parks.geojson")

gj_potholes = sf::st_read(cityworks_potholes_file, quiet = TRUE ) %>% st_transform(2264)

gj_parks = sf::st_read(raleigh_parks_file, quiet = TRUE ) %>% st_transform(2264)

#
# Load the geojson files
# change the coordinate system to 2264
# filter objects that belong to RALEIGHT
# --------------------------------------------
gj_raleigh <- sf::st_read(raleigh_corporate_limits_file, quiet = TRUE) %>% 
  st_transform(2264) %>% 
  filter( SHORT_NAME == 'RAL' )

head(gj_raleigh) %>% select(-ORDINANCE_NUMBER, -EFFECTIVE_DATE, -SHAPEAREA ) %>% st_drop_geometry() %>%
  kable() %>% kable_styling(bootstrap_options = c("striped", "hover"))

OBJECTID	SHORT_NAME	LONG_NAME	SHAPELEN
3451895	RAL	RALEIGH	6316.925
3452243	RAL	RALEIGH	2973.118
3452244	RAL	RALEIGH	10043.695
3452245	RAL	RALEIGH	1351.472
3452246	RAL	RALEIGH	9113.943
3452247	RAL	RALEIGH	9077.708

We compute the area of the polygonal representation and validate by checking against Wikipedia’s reported area. They are very close.

# Compute the total square miles of the polygons.
# The NAD83 North Carolina projection uses square ft.
# ------------------------------------------------------
area_of_polygons = st_area(gj_raleigh)

sprintf( "Raleigh Area is: %.2f square miles.  Wikipedia gives: 147.64 sq mi" , sum(area_of_polygons) / ( 5280^2)  )

## [1] "Raleigh Area is: 149.06 square miles.  Wikipedia gives: 147.64 sq mi"

The square mile area for most areas look accurate. However, note that they show area inside Wake County. Thus, Durham has less than 1 mile inside Wake County but actual area is over 100 squared miles.

a = sf::st_read(raleigh_corporate_limits_file, quiet = TRUE) %>%   st_transform(2264) 

a = a %>% mutate( my_area = st_area(a)) %>% mutate( sqmiles = my_area/ (5280^2)) %>% st_drop_geometry() %>%
   select(SHORT_NAME, LONG_NAME, sqmiles) %>% group_by(SHORT_NAME, LONG_NAME) %>% summarize( sqmiles = sum( sqmiles)) 

## `summarise()` has grouped output by 'SHORT_NAME'. You can override using the `.groups` argument.

attributes( a$sqmiles ) = NULL

a %>% kable(digits = 2, caption = "Square Miles of Towns inside Wake County")

Square Miles of Towns inside Wake County

SHORT_NAME	LONG_NAME	sqmiles
ANG	ANGIER	0.62
APE	APEX	24.82
CAR	CARY	59.04
CLA	CLAYTON	0.09
DUR	DURHAM	0.26
FUQ	FUQUAY-VARINA	18.44
GAR	GARNER	17.64
HOL	HOLLY SPRINGS	18.20
KNI	KNIGHTDALE	8.20
MOR	MORRISVILLE	8.86
RAL	RALEIGH	149.06
ROL	ROLESVILLE	6.15
WAK	WAKE FOREST	19.09
WEN	WENDELL	6.47
ZEB	ZEBULON	5.65

2 Visualization with GGPLOT and related libraries

2.1 Plotting the City and Base Layer

ggplot and geom_sf with no other arguments.

gj_raleigh %>% ggplot() + geom_sf() + labs(title = "Raleigh - Plain Map")

Fill the interior with color and add a border in red.

gj_raleigh %>% ggplot() + geom_sf( fill = "skyblue", color = "darkred", size = 0.1) + 
  labs(title = "Raleigh City Limits in Color")

Let’s put a basemap tile underneath and compass rose and alpha blend.

gj_raleigh %>% ggplot() + geom_sf( fill = "skyblue", color = "darkred") + 
  labs(title = "Raleigh City:  Basemap , Compass, Alpha Blending") +
  annotation_map_tile(type="osm", progress = "none", alpha = 0.5 ) +
  annotation_north_arrow(location="bl", which_north = "true")

## Loading required namespace: raster

2.2 Plotting Point Data and Cities As Layers

Here is a plot of all potholes in Raleigh Cityworks database.

gj_raleigh %>% ggplot() + geom_sf( fill = "skyblue", color = "darkred") + 
  labs(title = "Raleigh City: Basemap, Boundary and Potholes") +
  geom_sf(data=gj_potholes, color = "yellow" , size = 0.1 ) +
  annotation_map_tile(type="osm", progress = "none", alpha = 0.5 )

2.3 Mapping Parks and Cities as Layers

Here is a plot of all city parks in Raleigh database.

gj_raleigh %>% ggplot() + geom_sf( fill = "skyblue", color = "darkred") + 
  labs(title = "Raleigh City: Basemap, Boundary and Parks") +
  geom_sf(data=gj_parks, color = "darkgreen" , fill = "darkgreen") +
  annotation_map_tile(type="osm", progress = "none", alpha = 0.5 )

It appears that Forest Ridge Park (in North Raleigh) and Lake Wheeler Park (South Raleigh) are outside of City limits. Lake Wheeler is a large reservoir (650 acres water and 150 acres park). It is the primary water supply for Raleigh. It may be desirable to drop these two large parks since they fall outside the town limits.

gj_parks %>% select( NAME, PARK_TYPE, CAC, MAP_ACRES) %>% 
  st_drop_geometry() %>% arrange(desc(MAP_ACRES)) %>%
  kable(caption="Parks in Raleigh by Area", digits = 1 ) %>%
  kable_styling(bootstrap_options = c("striped", "hover"))

Parks in Raleigh by Area

NAME	PARK_TYPE	CAC	MAP_ACRES
Lake Wheeler	Metro	NA	873.9
Forest Ridge	Metro	NA	586.8
Lake Johnson	Metro	West	472.4
Dorothea Dix Park	Metro	Southwest	308.0
Durant Nature	Nature Preserve	North	241.6
Hwy 50 - Beaverdam	Special	NA	212.2
Walnut Creek South	Metro	South	204.7
Buffaloe Road Athletic	Metro	Northeast	165.6
Annie Louise Wilkerson, MD Nature Preserve	Nature Preserve	NA	157.6
Pearl Road	Special	South	155.0
Horseshoe Farm	Nature Preserve	Forestville	146.3
Shelley Lake - Sertoma	Metro	North	144.8
Marsh Creek	Community	Northeast	143.7
Thornton Road Property	Community	Forestville	130.6
Walnut Creek Athletic Complex	Metro	Southeast	104.8
Alvis Farm	Community	Northeast	97.9
Anderson Point	Community	Southeast	89.6
Milburnie	Community	Northeast	88.2
Leonard Tract	Community	North	83.6
Millbrook-Exchange	Community	North	69.5
Pullen	Metro	Hillsborough-Wade	66.4
Leesville	Community	Northwest	57.6
Barwell Road	Community	Southeast	54.5
Lake Lynn	Community	Northwest	52.0
Baileywick	Community	North	50.2
Hodges Mill Creek Property	Community	Forestville	49.2
Mount Herman	Special	Northwest	48.7
Laurel Hills	Community	Northwest	48.2
Biltmore Hills	Community	South	46.7
Walnut Creek Wetland Park	Greenway	South Central	45.9
Lions	Community	East	41.4
Carolina Pines	Community	Southwest	38.7
Cedar Hills	Neighborhood	Midtown	38.5
Watkins Road Property	Community	NA	38.4
Maybrook Forest	Neighborhood	Southeast	38.2
Worthdale	Community	Southeast	36.1
Strickland	Neighborhood	Northwest	36.1
North Hills	Neighborhood	Midtown	31.9
Optimist	Community	Midtown	30.7
Honeycutt	Neighborhood	NA	30.0
Abbotts Creek	Community	North	29.1
Chavis	Community	Central	28.9
Mount Hope Cemetery	Special	Central	28.6
Kyle Drive Property	Neighborhood	Northeast	27.2
Kiwanis	Neighborhood	Five Points	26.7
Green Road	Community	Atlantic	26.6
Forestville Road Property	Neighborhood	Forestville	26.3
Brookhaven	Neighborhood	Northwest	25.9
Eastgate	Neighborhood	Midtown	25.3
River Bend	Neighborhood	Forestville	25.0
Jaycee	Community	Hillsborough-Wade	24.9
Sanderford Road	Neighborhood	South	23.5
Spring Forest Road	Neighborhood	Northeast	21.8
Fred Fletcher	Neighborhood	Five Points	21.2
Sunnybrook Road Property	Neighborhood	Southeast	20.6
Wooten Meadow	Neighborhood	Northwest	20.5
Glen Eden	Neighborhood	Northwest	20.4
Brentwood	Neighborhood	Atlantic	19.2
Sherwood Forest	Open Space	Southeast	18.6
Drewry Hills #2	Neighborhood	Midtown	18.4
Hill Street	Neighborhood	Northeast	16.5
Durant Annex	Special	North	15.1
Windemere Beaver Dam	Neighborhood	Hillsborough-Wade	14.8
Kentwood	Neighborhood	West	14.6
Devereux Meadows	Special	Mordecai	14.3
Erinsbrook Drive Property	Neighborhood	Northwest	13.3
Oakwood	Neighborhood	North Central	12.7
Claremont	Open Space	Glenwood	11.5
Drewry Hills	Open Space	Midtown	11.1
Fallon	Neighborhood	Five Points	10.3
Brier Creek	Community	Northwest	10.0
Canoe Launch at Falls Lake	Special	North	9.1
Southgate	Neighborhood	South	8.8
Williams	Neighborhood	North	8.7
Powell Drive	Neighborhood	West	8.6
Method	Neighborhood	West	8.3
Berkshire Downs West	Mini	Forestville	7.8
City Cemetery	Special	South Central	7.4
Roberts	Neighborhood	South Central	7.2
Poole Road Canoe Launch	Greenway	Southeast	7.2
Peach Road	Neighborhood	Southwest	7.0
Longview	Neighborhood	East	6.9
Rose Garden & Raleigh Little Theatre	Special	Hillsborough-Wade	6.8
Ridge Road	Neighborhood	Glenwood	6.8
Rothgeb	Open Space	Glenwood	6.7
Winthrop Drive	Neighborhood	Northwest	6.4
Highhill Road Property	Neighborhood	North	6.4
Eliza Pool	Neighborhood	Southwest	6.2
Poole Road Property	Neighborhood	Southeast	6.0
Lt. Col. George F. Marshall Memorial Park	Special	Glenwood	5.9
Parnell	Open Space	Southeast	5.6
Kaplan	Neighborhood	West	5.2
3800 Rock Quarry Road	Neighborhood	South	5.0
Five Points Center for Active Adults	Special	Five Points	4.9
Jackson	Open Space	West	4.8
Halifax	Community	Mordecai	4.6
Hymettus Woods	Special	Hillsborough-Wade	4.5
Apollo Heights	Neighborhood	Southeast	4.3
Kingwood Forest	Neighborhood	South	4.2
Joslin Garden	Special	Glenwood	4.2
Moore Square	Special	Central	4.1
Nash Square	Special	Central	4.1
Cowper Drive Median	Open Space	Five Points	3.9
Lockwood	Special	East	3.8
Municipal Building	Special	Central	3.7
Isabella Cannon	Neighborhood	Hillsborough-Wade	3.5
West Park	Open Space	Hillsborough-Wade	3.4
Lassiter Mill	Greenway	Glenwood	3.2
Idolbrook	Open Space	North	3.2
Tarboro Road	Neighborhood	North Central	3.2
Mordecai Square	Special	Mordecai	3.2
Chavis Way	Greenway	South Central	3.1
Long Acres	Open Space	Southeast	3.0
West Lake	Open Space	Glenwood	3.0
Edna Metz Wells	Special	Hillsborough-Wade	2.9
FEMA HMGP Phase 1 - 1a	Open Space	Midtown	2.5
Civic Center Parking Lot	Special	Central	2.5
Mary Belle Pate	Neighborhood	Southwest	2.4
Martin L King Jr Memorial	Special	South Central	2.4
Avent Ferry Rd	Open Space	West	2.3
Buck Jones	Open Space	West	2.3
FEMA HMGP Phase 1 - 1b	Open Space	Midtown	2.2
Smallwood	Open Space	Hillsborough-Wade	2.1
Latta University Historic	Special	Hillsborough-Wade	2.0
FEMA HMGP Phase 1 - 3 Nobel	Open Space	Five Points	1.9
Forest	Open Space	Hillsborough-Wade	1.9
Walnut Terrace	Special	Central	1.7
Dixon	Special	Midtown	1.7
Roanoke	Neighborhood	Five Points	1.6
Marshall	Open Space	Mordecai	1.6
John Winters	Greenway	South Central	1.5
King William	Open Space	East	1.5
Chamberlain	Neighborhood	Hillsborough-Wade	1.4
3602 Woodlea Dr	Open Space	Atlantic	1.4
Kimbrough	Open Space	Five Points	1.3
FEMA HMGP Phase 1 - 5	Open Space	North	1.2
John P Top Greene	Neighborhood	Central	1.2
Meadowbrook	Open Space	Mordecai	1.2
Barmettler	Open Space	Hillsborough-Wade	1.2
FEMA HMGP Phase 1 - 2	Open Space	Midtown	1.1
FEMA HMGP Phase 1 - 4b	Open Space	South	1.0
Charlotte H Green	Neighborhood	Glenwood	1.0
Beckana	Open Space	Glenwood	1.0
FEMA HMGP Phase 3 - 1	Open Space	Midtown	1.0
O’Rorke-Catholic Cemetery	Special	North Central	1.0
Poplar Spring	Open Space	Mordecai	1.0
Longview Lake	Open Space	East	0.9
East & West Gardner Street	Open Space	Hillsborough-Wade	0.9
Davie Street	Mini	South Central	0.9
FEMA HMGP Phase 1 - 7	Open Space	Southwest	0.8
Culpepper Circle	Open Space	East	0.8
Dacian	Special	Southeast	0.7
Mordecai Annex	Special	Mordecai	0.7
FEMA HMGP Phase 1 - 10	Open Space	Midtown	0.7
FEMA HMGP Phase 1 - 3 Ann St	Open Space	Five Points	0.7
Tucker House	Special	North Central	0.7
Six Oaks	Open Space	Hillsborough-Wade	0.7
LeVelle Moton	Mini	North Central	0.6
Pollock	Neighborhood	Hillsborough-Wade	0.6
Caraleigh	Mini	Southwest	0.6
Furches	Open Space	Hillsborough-Wade	0.5
Mayview	Open Space	Hillsborough-Wade	0.5
Chester & Oberlin	Open Space	Hillsborough-Wade	0.5
Glenwood & Wake	Open Space	Five Points	0.5
Pasquotank & Granville	Open Space	Glenwood	0.5
Mordecai	Mini	Mordecai	0.5
FEMA HMGP Phase 1 - 6	Open Space	Midtown	0.5
Compiegne	Mini	Hillsborough-Wade	0.5
Varnell	Mini	Glenwood	0.4
Municipal Building Green	Mini	Central	0.4
Quail Hollow	Open Space	Midtown	0.4
Spring	Mini	West	0.4
Fenton	Open Space	East	0.4
Quarry Street	Mini	South Central	0.4
FEMA HMGP Phase 1 - 4a	Open Space	South	0.3
FEMA HMGP Phase 1 - 9	Open Space	Glenwood	0.3
Hertford Village	Mini	Southwest	0.3
Lenoir Street	Mini	Central	0.3
FEMA HMGP Phase 3 - 2	Open Space	Midtown	0.3
Bragg Street	Mini	Central	0.3
Junious N. Sorrell	Mini	Central	0.3
FEMA HMGP Phase 1 - 8	Open Space	Midtown	0.3
Yadkin Circle	Open Space	Midtown	0.3
Longstreet	Special	North	0.3
Fisher Street	Mini	North Central	0.3
FEMA HMGP Phase 1 - 3b	Open Space	Five Points	0.2
Market Plaza	Special	Central	0.2
FEMA HMGP Phase 1 - 3a	Open Space	Five Points	0.2
Exchange Plaza	Special	Central	0.2
Dogwood	Open Space	Northeast	0.2
FEMA HMGP Phase 1 - 3c	Open Space	Five Points	0.2
King Charles & Bertie	Open Space	East	0.2
Chatham & Stevens	Open Space	East	0.2
Oakwood Common	Mini	North Central	0.1
New Bern Place	Special	Central	0.1
Vallie Henderson	Special	North Central	0.1
Pope House	Special	Central	0.1
Carver	Open Space	North Central	0.1
Raymond G. Lanier	Mini	Central	0.1
Progress Energy Center	Special	Central	0.0
Fayetteville St	Special	Central	0.0
Convention Center	Special	Central	0.0
Greystone Recreation Center	Neighborhood	North	0.0
City Plaza	Special	Central	0.0
City of Raleigh Museum	Special	Central	0.0

2.4 Geomapping of Assault Incidents in Raleigh

gj_assault_geocoded = st_read(paste0(data_dir, "EXP_EDA_RALEIGH_assaults_Aug2021.geojson" ) )

## Reading layer `EXP_EDA_RALEIGH_assaults_Aug2021' from data source `/Volumes/GDRIVE_SSD/homes/alex/datascience/698_CAPSTONE_2021_FALL/project_data/EXP_EDA_RALEIGH_assaults_Aug2021.geojson' using driver `GeoJSON'
## Simple feature collection with 42305 features and 21 fields
## Geometry type: POINT
## Dimension:     XY
## Bounding box:  xmin: 2004513 ymin: 681334.3 xmax: 2148277 ymax: 808839.6
## Projected CRS: NAD83 / North Carolina (ftUS)

head(gj_assault_geocoded)

gj_raleigh %>% ggplot() + geom_sf( fill = "skyblue", color = "darkred") + 
  labs(title = "Raleigh City: Basemap, Boundary and Crime") +
  geom_sf(data=gj_assault_geocoded, color = "yellow" , size = 0.1 ) +
  annotation_map_tile(type="osm", progress = "none", alpha = 0.5 )

2.5 Crime Density Maps by Year

2.5.1 Crime in 2014

This was a partial year

gj_raleigh %>% ggplot() + geom_sf( fill = "skyblue", color = "darkred") + 
  labs(title = "Raleigh City: Crime Map 2014") +
  layer_spatial(data=gj_assault_geocoded %>% filter(reported_year==2014), color = "yellow" , size = 0.1 ) +
  annotation_map_tile(type="osm", progress = "none", alpha = 0.5 ) 

2.5.2 Crime in 2015

This was a full year

this_year = 2015

gj_raleigh %>% ggplot() + geom_sf( fill = "skyblue", color = "darkred") + 
  labs(title = paste0("Raleigh City: Crime Map ", this_year ) ) +
  layer_spatial(data=gj_assault_geocoded %>% filter(reported_year==this_year), color = "yellow" , size = 0.1 ) +
  annotation_map_tile(type="osm", progress = "none", alpha = 0.5 ) 

2.5.3 Crime in 2016

This was a full year

this_year = 2016

gj_raleigh %>% ggplot() + geom_sf( fill = "skyblue", color = "darkred") + 
  labs(title = paste0("Raleigh City: Crime Map ", this_year ) ) +
  layer_spatial(data=gj_assault_geocoded %>% filter(reported_year==this_year), color = "yellow" , size = 0.1 ) +
  annotation_map_tile(type="osm", progress = "none", alpha = 0.5 ) 

2.5.4 Crime in 2017

This was a full year

this_year = 2017

gj_raleigh %>% ggplot() + geom_sf( fill = "skyblue", color = "darkred") + 
  labs(title = paste0("Raleigh City: Crime Map ", this_year ) ) +
  layer_spatial(data=gj_assault_geocoded %>% filter(reported_year==this_year), color = "yellow" , size = 0.1 ) +
  annotation_map_tile(type="osm", progress = "none", alpha = 0.5 ) 

2.5.5 Crime in 2018

This was a full year

this_year = 2018

gj_raleigh %>% ggplot() + geom_sf( fill = "skyblue", color = "darkred") + 
  labs(title = paste0("Raleigh City: Crime Map ", this_year ) ) +
  layer_spatial(data=gj_assault_geocoded %>% filter(reported_year==this_year), color = "yellow" , size = 0.1 ) +
  annotation_map_tile(type="osm", progress = "none", alpha = 0.5 ) 

2.5.6 Crime in 2019

This was a full year

this_year = 2019

gj_raleigh %>% ggplot() + geom_sf( fill = "skyblue", color = "darkred") + 
  labs(title = paste0("Raleigh City: Crime Map ", this_year ) ) +
  layer_spatial(data=gj_assault_geocoded %>% filter(reported_year==this_year), color = "yellow" , size = 0.1 ) +
  annotation_map_tile(type="osm", progress = "none", alpha = 0.5 ) 

2.5.7 Crime in 2020

This was a full year

this_year = 2020

gj_raleigh %>% ggplot() + geom_sf( fill = "skyblue", color = "darkred") + 
  labs(title = paste0("Raleigh City: Crime Map ", this_year ) ) +
  layer_spatial(data=gj_assault_geocoded %>% filter(reported_year==this_year), color = "yellow" , size = 0.1 ) +
  annotation_map_tile(type="osm", progress = "none", alpha = 0.5 ) 

2.5.8 Crime in 2021

This was a partial year

this_year = 2021

gj_raleigh %>% ggplot() + geom_sf( fill = "skyblue", color = "darkred") + 
  labs(title = paste0("Raleigh City: Crime Map ", this_year ) ) +
  layer_spatial(data=gj_assault_geocoded %>% filter(reported_year==this_year), color = "yellow" , size = 0.1 ) +
  annotation_map_tile(type="osm", progress = "none", alpha = 0.5 ) 

2.6 Kernel Density Plots

The KDE code below does not work as modified. Need to think of a better solution.

ggplot(data=gj_assault_geocoded %>% filter(reported_year==2019) ) +
   stat_sf_coordinates() +
    coord_equal() +
   xlab('Longitude') + ylab('Latitude') +
  stat_density2d(aes(fill = ..level.., x = after_stat(x), y = after_stat(y)), 
                 alpha = 0.5 , h = 0.007, n = 500, geom = "polygon" ) +
  scale_fill_viridis_c() +
  annotation_map_tile(type="osm", progress = "none", alpha = 0.5 ) 
  theme(legend.position = 'none' )